Hippocrates of Cos, born around 460 BCE, was a historical physician from the island of Cos and a member of the Asclepiad guild. A contemporary of Socrates, he is traditionally credited with establishing medicine as a rational discipline based on observation. The Hippocratic Corpus is a collection of roughly 60 medical treatises written in Ionic Greek between the late fifth and third centuries BCE by multiple, anonymous authors. These works were later assembled under his name in the Hellenistic period. The historical Hippocrates’s own writings are lost and cannot be identified within the Corpus.
The Corpus comprises treatises on diverse medical topics. Major works include On the Sacred Disease, which argues epilepsy has natural causes; Airs, Waters, Places, on environmental influences on health; Epidemics, a collection of case histories; On the Nature of Man, which expounds the theory of the four humors; and The Oath, an ethical code for physicians. Other significant texts are On Ancient Medicine, Prognostic, Aphorisms, and several surgical manuals.
The Hippocratic Corpus represents the foundational text of Western medicine, establishing a systematic, naturalistic approach that sought physical causes for disease. Its key contributions include the development of clinical observation, the theory of the four humors, and the enduring ethical principles of the Hippocratic Oath.